Ignition coils are known for use in connection with an internal combustion engine such as an automobile engine. Ignition coils typically include a core around which is wound a primary winding. A secondary winding is wound around a secondary winding spool to surround the primary winding such that a high voltage is induced on the secondary winding when an electric current applied to the primary winding is stopped. One end of the secondary winding is a low voltage end which is connected to a ground terminal while the other end of the secondary winding is a high voltage end which is connected to a high voltage terminal which is in electrical communication with a spark plug, thereby delivering a spark-generating current to the spark plug.
Connecting the low voltage end and the high-voltage end of the secondary winding to their respective terminals may be complex and costly. In order to attach the low-voltage end of the secondary winding to the low-voltage terminal, the low-voltage end is wrapped onto the low-voltage terminal, and then dipped into solder in order to strip the wire and make the electrical connection. In order to attach the high-voltage end of the secondary winding to the high-voltage terminal, the high-voltage end of the secondary winding is wrapped onto the high-voltage terminal, and then dipped into solder in order to strip the wire and make the electrical connection. Due to the high-voltage terminal being at high-voltage in use, they typically need to be bent and formed to minimize electric field concentrations at the tip. In the case of both the low-voltage end and the high-voltage end of the secondary winding, the terminals need to be assembled to the spool and terminated, then formed in some manner. Furthermore, a resistor is typically added between the secondary winding and the spark plug in order to suppress radio frequency interference (RFI). The addition of a resistor adds additional cost to the system.
Korean Patent No. KR970005493 teaches using a conductive epoxy to provide electric communication between a terminal pin and an external terminal. However, the terminal pin must still be connected to the high-voltage end of the secondary winding in a conventional manner.
What is needed is an ignition coil which minimizes or eliminates one or more of the shortcomings as set forth above.